Green River, west of the continental divide, differs from the other towns in not having a characteristic railroad origin. Early residents plotted a town site, north of where the Overland stage route crossed the Green River, before the railroad arrived. Settlement did not begin until July 1868, when some men who hoped to profit by the boom the railroad was likely to bring, laid out a town. By September, 2000 people occupied the site. When the Union Pacific arrived, however, its builders gave the speculators no attention, but bridged the river and moved on as fast as possible. The railroad deserted the town only to return when it realized its good location as a division point.

Highway travelers found a town of 2140, the Sweetwater county seat, and division headquarters for the railroad. In 1924 Green River had four hotels, garages, auto supplies, tires, electricity and water, two banks, 15 businesses, one newspaper and two telephone companies.

In later years it billed itself the hub of the Wyoming Route on US Highway 30; south to Flaming Gorge Project, Utah Highway 42 and 44; to Colorado Highway 40; north to Wind River Mountains and Yellowstone and Grand Teton National Parks; and west to the dividing highway northwest to Idaho, along the old Oregon Trail, and southwest to Utah.

Through the years, highway traffic helped stabilize the town's economy. Interstate 80 continues the future of Green River (population 14,000 in 1985) as a prosperous trona mining and transportation town that straddles the river of the same name. Interstate 80 cuts a swath just north of town, plunging through tunnels beneath memorable badlands topography. The large UP Railroad yard slices the town in half.

Just for Railfans. There is a pedestrian bridge over the yard that gives you a great spot for photography.